1. Field of the Invention
The present invention relates to a mechanical pencil provided with a double-chuck mechanism and a side-knock operating mechanism.
2. Description of the Related Art
Although there have been double-chuck mechanical pencils provided with double-chuck mechanisms, and side-knock type mechanical pencils provided with side-knock type lead control mechanisms, there has not been proposed any mechanical pencil provided with both a double-chuck mechanism and a side-knock operating mechanism. A double-chuck mechanical pencil provided with a front lead chuck and a back lead chuck, wherein a lead is adapted to be held by the front and back lead chucks, needs a turning motion inhibiting mechanism for inhibiting the front and back lead chucks from turning relative to each other because the lead is twisted and broken if either the front or the back lead chuck is turned.
A side-knock type mechanical pencil is provided with a side knock member which is moved along a slope, formed on a slide member, to project a lead. In the side-knock mechanical pencil, it is difficult to secure a space for a long stroke of the side knock member, and assembly is difficult and there is the possibility that an operation for knocking the side knock member cannot be properly achieved if the slide member turns relative to a barrel. Therefore, the side-knock mechanical pencil needs a turning motion inhibiting mechanism for inhibiting the slide member from turning. Accordingly, the use of a double-chuck mechanism and a side-knock type lead control mechanism in combination entails various technical problems and makes the construction of a mechanical pencil complex.